Highway vibration after lift

[danenglish2]

My gladiator has developed a vibration/wobble at 60 mph+ after installing my lift and wheels. The lift is an EVO enforcer overland 4.5" stage 4. Replaced trackbars, swaybars, control arms with front control arm drop and rear trackbar lift. Wheels are method trail series 17" with nitto trail grappler 37s. I've set the control arms and trackbars to the recommended length. I've torqued everything according to spec. Still tracks straight. Alignment seems reasonably close (planning to get a professional alignment, but they're booked 3 weeks out). Rear driveline is close to zero degrees. What else am I missing? Stock steering stab is too weak?

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[Renegade]

Sounds like out of balance tires to me...

 

[danenglish2]

Sounds like out of balance tires to me...

Hmm, I ordered these tires/wheels fully mounted and balanced from 4WP, but anything is possible. I'll put that on the checklist.

 

[Renegade]

Hmm, I ordered these tires/wheels fully mounted and balanced from 4WP, but anything is possible. I'll put that on the checklist.

Do you still have your stock tires and wheels? Have you tried swapping them on the see if the vibration goes away?

 

[danenglish2]

Do you still have your stock tires and wheels? Have you tried swapping them on the see if the vibration goes away?

I do... but I think I'd need spacers because of the backspacing.

 

[danenglish2]

Do you still have your stock tires and wheels? Have you tried swapping them on the see if the vibration goes away?

Hey you were right! I swapped wheels with my wrangler (35's) and the vibration went away. Thanks for the suggestion.

 

[ShadowsPapa]

My gladiator has developed a vibration/wobble at 60 mph+ after installing my lift and wheels. The lift is an EVO enforcer overland 4.5" stage 4. Replaced trackbars, swaybars, control arms with front control arm drop and rear trackbar lift. Wheels are method trail series 17" with nitto trail grappler 37s. I've set the control arms and trackbars to the recommended length. I've torqued everything according to spec. Still tracks straight. Alignment seems reasonably close (planning to get a professional alignment, but they're booked 3 weeks out). Rear driveline is close to zero degrees. What else am I missing? Stock steering stab is too weak?

Recommended length doesn't mean on YOUR truck the caster is correct.
I'd get caster checked.
Did you set toe? You say "seems reasonably close" - based on? Wobble means it could be out, that's a possible indication.
Bad toe setting, bad caster, can cause wobble.
You set the lower control arms to recommended length - was that length taking into consideration the control arm drop?
EDIT -
I see you found it in the wheels - why not before, I wonder?

 

[danenglish2]

Recommended length doesn't mean on YOUR truck the caster is correct.
I'd get caster checked.
Did you set toe? You say "seems reasonably close" - based on? Wobble means it could be out, that's a possible indication.
Bad toe setting, bad caster, can cause wobble.
You set the lower control arms to recommended length - was that length taking into consideration the control arm drop?
EDIT -
I see you found it in the wheels - why not before, I wonder?

Like I mentioned, I do have an appt for a professional alignment in a couple weeks. I did not change the toe, but I did check it using a tape measure and it is indeed 1/8" toe-in. Lift did not affect the factory toe. Caster could be off, although it does track straight on the highway. The directions said to add 3/8" to the control arms if using the drop, which I did.

 

[ShadowsPapa]

Cool - and yes, toe should not change because these won't be impacted by any other change.
We've seen caster off from the factory - not common, but - a stack-up of tolerances can do it. As long as it is tracking straight and doesn't want to wander or pull, sounds like you have it under control and did great.

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